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  • Read operation according to a key
  • Checking the password
  • Miscellaneous
  • Comparison between HReadFirst and HFirst
  • Locks
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Stored procedures
Sets the position on the first record of a data file according to the specified browse item. The record is not read.
The number of the current Record is changed only when it is returned by the HRecNum function. For the functions handling by default the number of the current Record (functions HDelete, HRead, HModify, ...), the value of this number is not updated: you must use HRecNum(). For example: not to do:
HDelete(Client)
but
HDelete(Client, HRecNum())
get is from the smallest to the largest value of the path heading (see notes for details).
Caution: The record loaded in memory is not modified. The HFSQL variables (Customer.Name for example, which means the Name item of Customer file) are not updated.
In general, the HFirst function is used to position oneself in the data file to perform a loop among the records corresponding to a condition. HNext is used to position on the next record corresponding to the condition.
Several cases may occur after the call to HFirst:
  • a record corresponding to the condition was found: function HFound returns True
  • the data file is empty or there is no record corresponding to the condition: function HOut returns True
Remarks:
  • By default, HSeekFirst and HSeekLast are used to perform an exact-match search.
  • By Default, the function HFirst performs a generic search.
Versions 15 and later
Android This function is now available for Android applications.
New in version 15
Android This function is now available for Android applications.
Android This function is now available for Android applications.
Versions 17 and later
iPhone/iPad This function is now available for iPhone/iPad applications.
New in version 17
iPhone/iPad This function is now available for iPhone/iPad applications.
iPhone/iPad This function is now available for iPhone/iPad applications.
Versions 18 and later
Android Widget This function is now available in Android widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
New in version 18
Android Widget This function is now available in Android widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
Android Widget This function is now available in Android widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
Remark: From version 19, HFSQL is the new name of HyperFileSQL.
Versions 21 and later
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
New in version 21
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.

get is done from the smallest to the largest value of the path heading (see remarks for details).
Caution: The record loaded in memory is not modified. The HFSQL variables (Customer.Name for example, which means the Name item of Customer file) are not updated.
In general, the HFirst function allows you to position yourself in the data file to loop get with the HNext function.
Several cases may occur after the call to HFirst:
  • the data file is empty or there is no record corresponding to the filter (defined by function HFilter): HOut returns True.
  • the function tries to lock a record that is already locked in read-only: HErrorLock returns True and HOut returns True.
    Java Access by JDBC: The management of locks is not available for databases accessed by JDBC.
Versions 15 and later
Android This function is now available for Android applications.
New in version 15
Android This function is now available for Android applications.
Android This function is now available for Android applications.
Versions 17 and later
iPhone/iPad This function is now available for iPhone/iPad applications.
New in version 17
iPhone/iPad This function is now available for iPhone/iPad applications.
iPhone/iPad This function is now available for iPhone/iPad applications.
Versions 18 and later
Android Widget This function is now available in Android widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
New in version 18
Android Widget This function is now available in Android widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
Android Widget This function is now available in Android widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
Remark: From version 19, HFSQL is the new name of HyperFileSQL.
Versions 21 and later
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
New in version 21
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
Example
HFirst(Client, Nom)
WHILE HOut() = False
// Traitement de l'enregistrement
HNext(Client, Nom)
END
Syntax
<Result> = HFirst([<Data file> [, <Search key item>] [, <Options>]])
<Result>: Boolean
  • True if the position was set,
  • False if an error occurred. This problem can be caused by:
    • a positioning problem (empty data file, ...): HFound returns False and HError returns 0.
    • an error: HError returns an integer other than 0. HErrorInfo returns more details.
<Data file>: Optional character string
Name of the data file used. If this parameter is an empty string (""), HFirst manipulates the last data file used by the last HFSQL function (function starting with "H").
<Search key item>: Optional character string
Name of key item used to browse the data file. If this name is not specified, the HFirst function will handle the last path field used on this data file by the last HFSQL management function (function starting with the letter H). If this item does not exist, the best browse item is automatically used.
<Options>: Optional constant
Configures the lock set on the record selected by HFirst:
hLockNoNo lock: the record can be read or modified by another application.
Java Access by JDBC: This constant is not available.
hLockWriteLock in write mode: the selected record can be read by another application but it cannot be modified by another application.
Java Access by JDBC: This constant is not available.
hLockReadWriteLock in read/write: the selected record cannot be read or modified by another application.
OLE DB Lock in write mode: the selected record can be read by another application but it cannot be modified by another application. Equivalent to hLockWrite.

Java Access by JDBC: This constant is not available.
hKeepFilterThe path will take into account the filter set up with the HFilter function, even if the path key used is not optimized for the filter. Reminder: function HFilter returns the optimized path key for the filter.
Caution: In this case, performance issues may arise for large data files.
Hyper File 5.5 This variable cannot be used.
hNoRefresh
OLE DB The table or query content will not be refreshed. All the saved positions are stored. If this parameter is not specified, HFirst reinitializes the browse for the specified item: the content of table or query is refreshed with the data found in the OLE DB database. All the saved positions are lost. The position will be restored according to the value of best item.
Remark: The browses and the positions saved on the other items are not affected.
Java Access by JDBC: The management of locks is not available for databases accessed by JDBC.
OLE DBNative Connectors (Native Accesses) The lock options will have no effect if the locks are not supported by the OLE DB provider or by the Native Connector.
OLE DB The lock mode specified by HFirst will remain effective during the calls to HPrevious and HNext.
To modify the lock mode, you must use:
Native Connectors (Native Accesses) Oracle: a different lock mode can be specified for each record. However, if a transaction was started by SQLTransaction before setting the lock, the lock will only be released at the end of the transaction (SQLTransaction associated with sqlCommit or sqlRollback).
Hyper File 5.5 The lock options are ignored. Use the lock functions (HLockRecNum) kept for backward compatibility.
Remarks

Read operation according to a key

HFirst positions on the record with the smallest key value.
The sort order is the one that was specified in the analysis for this key.
If duplicates are found, HFirst sets the position on the first "duplicate" record according to the sequence of record numbers.
WINDEVWEBDEV - Server codeReports and QueriesUniversal Windows 10 AppiPhone/iPadJavaUser code (UMC)AjaxHFSQLHFSQL Client/ServerHyper File 5.5

Checking the password

If function HFirst is the first function handling the data file specified, the password check is performed when of the data file is opened.
If the password is incorrect, HErrorPassword returns True and HOut returns True.

Miscellaneous

  • The current record number is returned by HRecNum.
  • The HChangeKey function allows you to change the route key, while remaining positioned on the current Record.

Comparison between HReadFirst and HFirst

HFirst does not read the record: therefore, HFirst is faster than HReadFirst.
WINDEVWEBDEV - Server codeWINDEV MobileReports and QueriesUniversal Windows 10 AppiPhone/iPadUser code (UMC)AjaxHFSQLHFSQL Client/ServerHyper File 5.5OLE DBNative Connectors (Native Accesses)

Locks

By default (<Options> not specified), the record is not locked.
If a lock is requested (hLockWrite or hLockReadWrite constant), the position will be set on the record only if it is not already locked.
Component: wd270hf.dll
Minimum version required
  • Version 9
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